iwlwifi: mvm: new NVM format in family 8000

Support the changes below:
- Fields and sections structure were changed.
- the NVM file built from DWord instead of Words.
- sections header format was changed.

Signed-off-by: Eran Harary <eran.harary@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>